an almost frictionless bearing consisting of two or more rollers on a flexible metal band, that serves as a suspension system in various devices, as switches, valves, pumps, etc.
Origin of rolamitearbitrary coinage based on roll
A mechanism consisting of two or more hard cylindrical rollers with a flexible nonstretching band looped around them, so that the rollers move against each other with very little friction.
Origin of rolamiterol(l) + -amite, of unknown origin.
When rotated as indicated in the top illustration, the rollers and metal strip will move to the right.